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Friday, April 24, 2020

It's been a little while since I've posted an update on the PHP Cloud Native Buildpacks. The good news is that lots of progress has been made. We've basically achieved feature parity with the old PHP buildpack and I believe the PHP CNB's should be working for most apps now!

Add a file to the root called buildpack.yml. In that file, add the following:---php: webdirectory: public

This will tell the buildpack the location of the files that we want it to serve.

Create the folder .php.ini.d and in it put the file symfony.ini. Inside that file, add the line: variables_order = "EGPCS". This tells PHP that we want the $_ENV superglobal. I'm not a Symfony expert, but it seems to be required for Symfony to configure itself from actual environment variables, which we'll be doing.

Now, from the root of our application directory we just run pack build -b paketo-buildpacks/php -e APP_ENV=prod symfony-5-demo to build an image.

Breaking it down:

pack build is the command to build an image from Cloud Native Buildpacks

the -b flag indicates which Cloud Native Buildpacks to use. In this case, we point it to the meta buildpack for PHP. Meta buildpacks are collections of Cloud Native Buildpacks.

the -e flag set an environment variable picked up by Symfony during build. It tells it that we're doing a production build.

the last bit is the image name we want to create

Lastly, we can run our image with docker run -e PORT=8080 -p 8080:8080 -e APP_ENV=prod symfony-5-demo.

Breaking it down:

docker run will run your image

-e sets the PORT environment variable which tells the buildpack what port it should have the app listen to.

-p tells Docker that we want to expose port 8080. This needs to match the value of PORT so that the port on which the app is listening matches the port on which docker is allowing traffic.

the second -e again tells Symfony that we're running in production mode

the last bit is the image name to run, this should match the image name we used with pack build.

At this point, you can go to http://localhost:8080/ in your browser and access the Symfony Demo App that's been built with Cloud Native Buildpacks and is running inside your Docker container.

Some final notes:

By default, it's going to run with PHP's built-in web server. That's not very "production", so we can add Nginx or Apache Web Server by adding the line webserver: httpd or webserver: nginx to buildpack.yml (add it under the php: block). That's it. No server configuration files required. The PHP Cloud Native Buildpacks handle it all for you.

The first time you run pack build, it will be slow. It needs to download resources like the build & run images, plus of course it needs to download PHP itself. After the first time, things will speed up dramatically. The images will exist locally and PHP downloads are smartly cached. With downloads cached, a full build takes about 10 seconds on my laptop.

That's it. Hope you all enjoy. Feel free to raise any feedback on Github.

Sunday, September 08, 2019

In my previous post, I talked about how to use the PHP Cloud Native buildpacks. It was not super tricky but required some manual work to set up. This is because the PHP CNBs were not, at the time, part of an official builder.

Notice how PHP is now included in the Cloud Foundry cflinuxfs3 builder.

So now, instead of all the work I had you doing in my last post, you can just run `pack build --builder "cloudfoundry/cnb:cflinuxfs3"`. The builder will automatically select the PHP CNBs, because it sees you're trying to build a PHP app. The result will be an image you can run with `docker run -it -e PORT=8080 -p 8080:8080 image-name`, just like in my previous post.

That's it! If you'd like to understand the output a bit more, keep reading. Otherwise go and enjoy!

If you're curious about the output, the interesting new bit is the DETECTING phase. In the previous post, we manually specified just the PHP CNBs, so that's all you'd see in the output. Now, we see many CNBs running, but only the PHP CNBs will be selected and actually run at build time.

Thursday, July 04, 2019

At work, I've been helping to rewrite the PHP buildpack as a set of Cloud Native Buildpacks. The PHP CNBs are coming together, current quality is alpha, but I think they're ready enough for people to try them out and report how they work for you. This post has instructions and a demo to use the PHP CNBs.

But first, a slight digression.

A little about the architecture of the PHP CNBs. The previous PHP buildpack has been decomposed into a set of five PHP CNBs, two of which are optional. There are php-cnb, php-composer-cnb, httpd-cnb, nginx-cnb and php-web-cnb.

Here's a rough description of each:

php-cnb provides PHP binaries, that's it.

php-composer-cnb provides all the functionality related to Composer. It installs and runs Composer.

httpd-cnb provides Apache Web Server. It is optional.

nginx-cnb provides Nginx Web Server. It is optional.

php-web-cnb ties everything together. It generates the configuration for PHP, PHP-FPM, HTTPD and Nginx. It also contains the logic to generate start commands for various types of PHP apps. It can run PHP cli scripts, PHP's bundled web server, PHP-FPM plus HTTPD and PHP-FPM plus Nginx.

What's also super cool about these CNBs is that some of them like httpd-cnb and nginx-cnb can work all on their own. Want to stand up a proxy or a static site, httpd-cnb or nginx-cnb can be given an httpd.confor nginx.conf file and they'll run their respective server with that config for you. Similarly, you can mix and match CNBs. Don't want to use the PHP binaries provided by php-cnb, you could substitute another CNB that provides PHP. Pick the parts you like, replace the ones you don't with other things.

On to the show.

If you want to get started there's a little setup that you need to perform.

First, `git clone` these repos and optionally check out a release branch.

Third, install Docker if you don't have it already. Make sure it's running too.

Fourth, package up each buildpack that you'd like to use. In each folder that you cloned, you can run `./scripts/package.sh` and it will build the CNB (this requires Golang to be installed). Note the path at which the packaged CNB can be found. You'll need to pass this to the pack cli so it can find the buildpacks. To do that, run `export BUILDPACKS='--buildpack /path/to/buildpack1 --buildpack /path/to/buildpack2 ...'` and paste in the path to each buildpack you packaged. Order is important, use the order listed in the bullet list above.

If you'd like to build them all at once, you can run the following command from the directory where you cloned all of the repos:

This will run the package script for each CNB & then print out a list of the locations for each package. Simply copy the output, then run `export BUILDPACKS='paste output from command here'`. We set this as a convenience to make using the pack cli easier and the commands shorter.

At this point, you're all set to build some images. To do this, you run `pack build $BUILDPACKS -p /path/to/php/files`. This will build an image using the buildpacks that we've specified in our environment variable and it will use the PHP code that you've pointed to with the `-p` argument (you can skip `-p` if the files are in the current directory.

As `pack build` runs, you'll see each build pack run. If there are any errors the buildpack will fail and tell you what happened. If it succeeds, you'll end up with a docker image that you can run using the command `docker run`. For example, if you have a web app, you can `docker run -it -e PORT=8080 -p 8080:8080 `. The PORT env variable tells the web server which port it should listen to. That should match with the port that you expose using the `-p` flag.

Time for a full example.

Let's say you want to run PHP MyAdmin. The following is a demo of how you could do that. For simplicity sake, it spins up a Percona DB as well. That allows you to have something to connect to within PHP MyAdmin. If you already have a MySQL DB, you can skip that part and point `htdocs/config.inc.php` to your existing server (you could also skip the docker network bits, that just makes it easy to connect to the deployed Percona DB).

Download and run the Gist below. This will set everything up for you.

Here are the highlights:

Line #10 runs Percona

Lines #15 - #21 download PHP MyAdmin & configure `htdocs/config.inc.php`. If you want to adjust PHP MyAdmin's config, you can do so at this point.

At this point, you can go to http://localhost:8080 in your browser and you should be able to access PHP MyAdmin. Enter `root` and `hacKm3` as the credentials and you can access the database. If you edited the config to point to your own MySQL server, use the credentials for that server instead.

Last notes:

If you want to adjust the PHP MyAdmin config. Run `docker stop php-myadmin`. Edit `htdocs/config.inc.php` then run lines #45 & #48 again.

If you want to clean up & remove everything run `docker stop php-myadmin test-db` followed by `docker system prune --volumes`. The latter will clean up a bunch of things for you, be careful when running that if you are running other things with Docker.

Please provide any feedback about the PHP CNBs to the respective CNB Github page. Open an issue with your comments/questions. Thanks & hope you enjoy!

Sunday, February 17, 2019

In the past, I've worked with buildpacks through my time using Cloud Foundry. Cloud Foundry has first class support for buildpacks, which allows you to push code and let the buildpack handle the messy parts of actually running your code. Things like installing a language runtime, installing servers, etc...

Hello World

To get a basic app going, we need to do one more thing first. Obtain some buildpacks to use. So run `git clone https://github.com/buildpack/samples`, which is a repo that has a couple very basic sample buildpacks.

Sidebar. At the time of writing, the sample buildpack we're using has an error with it's metadata. You may not need to do this in the future. Edit `samples/hello-world-buildpack/buildpack.toml` and put in the following:

Now that we have buildpacks, we need an app to run. We'll create that now. Run `mkdir hello-world` and then `cd hello-world`. In that folder create `app.sh` and put the following in that file.

#!/bin/bash
while [ 1 -eq 1 ]; do
echo "Hello World!"
sleep 5
done

Last step, run `chmod 755 app.sh` to make it executable.

At this point, we now have a buildpack to use and our application code. It's time to run `pack` and make an image.

From our application directory run `pack build --buildpack $(cd ..; pwd)/samples/hello-world-buildpack/ hello-world-app` or replace `$(cd ..; pwd)/samples/hello-world-buildpack/` with the full path to the sample repo you cloned above. This will create an image called `hello-world-app` using the `hello-world-buildpack`, which does nothing (it's a no-op). The output should look something like this.

The interesting bits for now are DETECTING, where the buildpack's detection script runs. This buildpack doesn't do anything but we can see it's marked as "pass" which means the buildpack's build script will get a chance to run. Down below you can see that happening under BUILDING. This again does nothing, but echo a few directories where files reside during build. Legit buildpacks would use detect to determine when they should/shouldn't run and build to install things like runtimes, servers and all the stuff necessary to run your apps.

The output from above is a image that you can run. If you execute `docker images`, you'll see `hello-world-app` listed.

To run the updated app image, you can use the same command `docker run -it --name=hello hello-world-app bash app.sh` and you'll see the same output. However, if you run `docker run -it -e NAME=Daniel --name=hello hello-world-app bash app.sh` you'll see our enhancement.

We use Docker's ability to set environment variables to inject some data into our application. More importantly though, you can see that pushing updates and changes is the same process as you used before which makes integrating into build systems and CI/CD systems simple.

Summary

I hope you find getting started is easy. Once you get Docker & pack installed it's one command to stamp out an image using a buildpack and our application. Right now, that buildpack isn't doing anything, so it's not the best demonstration of why you'd want use buildpacks or the full power of them, but I hope this is enough to get you thinking about how this can integrate into your build flows, maybe your CI/CD system and how it can work for you.

My next post will be more practical. It'll dig into some actual buildpacks and show how you can use them to make images for actual applications, and I hope this will better showcase why you would want to use buildpacks.